Rhode Island Journeyman Plumber Practice Exam

What is the major cause of pipe corrosion?

1. Low temperatures

2. Presence of oxygen in water

3. High water pressure

4. All of the above

The correct answer is: Presence of oxygen in water

The major cause of pipe corrosion is generally attributed to the presence of oxygen in water. This is because oxygen can react with the metal of the pipes, leading to oxidation processes that form rust and other corrosive compounds over time. When water contains dissolved oxygen, it accelerates the corrosion process, particularly in metals like iron or steel, which are more susceptible to rusting. While low temperatures and high water pressure can also influence the rate of corrosion or create specific conditions that promote it, they are not the primary factors driving the corrosion process itself. Low temperatures may slow down chemical reactions, and high water pressure can lead to physical stress or mechanical wear that may compromise pipe integrity, but the presence of oxygen is a fundamental factor that directly contributes to corrosion. Thus, focusing on the presence of oxygen provides a clearer understanding of the root cause of pipe corrosion.